The long-term objective of the project is to understand spoken language processing - particularly speech perception - in linguistic context. Speech signals are unique in human experience because they are highly familiar, and have great practical significance in daily life. Therefore, it is not too surprising to find that people develop optimized processing strategies tuned specifically for speech. In this project, we study how this tuning process may be sensitive to linguistic structure. Cross-linguistic spoken language research is important because without it we are in danger of concluding that the phenomena found in one language (or even dialect) are somehow normative for speakers of other languages. Such a narrow understanding of 'normal' spoken language processing is likely to have a negative impact on clinical speech and hearing practice in a pluralistic society. Three lines of research will be pursued. The first involves the perceptual phenomenon called compensation for coarticulation. The research is designed to determine the extent to which linguistic knowledge impacts this process, using behavioral speech perception experiments with speakers of English and French (who have different native-language experience with high front vowels like [y]). The second set of experiments, with English, Dutch, and German speakers explores the role of segment, syllable, and word frequencies in speech perception. The aim here is also to explore the impact of linguistic knowledge on speech perception - particularly the possibility that frequency of exposure alters perception. The final set of experiments examines the impact of language-specific patterns of phonetic variability on perception. The overarching aim of the research project is to learn more about how one's linguistic experience shapes perceptual abilities. PUBLIC HEALTH RELEVANCE: This research is relevant for public health in two ways. First, it provides a clearer basic scientific understanding of the human ability to perceive speech. Second, it highlights ways that people who have different linguistic backgrounds may be expected to have different perceptual abilities. Both of these will improve training and practice in the speech and hearing clinic.